A DC programming heuristic applied to the logistics network design problem

This paper proposes a new heuristic method for the logistics network design and planning problem based on linear relaxation and DC (difference of convex functions) programming. We consider a multi-period, multi-echelon, multi-commodity and multi-product problem defined as a large scale mixed integer linear programming (MILP) model. The method is experimented on data sets of various size. The numerical results validate the efficiency of the heuristic for instances with up to several dozens facilities, 18 products and 270 retailers.     

重油催化裂化装置安全评价

运用道化学公司火灾、爆炸危险指数评价方法对广州石化重油催化裂化装置进行安全评价，定量地认识该装置的危险性，提出安全建议。     

电磁流量与示踪相关流量组合测井仪及其应用

在对电磁流量与示踪相关流量组合测井仪的基本原理、井下仪器结构、仪器工作方式、技术指标等内容进行详细阐述的基础上,进一步运用测井实例分析了电磁流量与示踪相关流量组合测井仪能把电磁流量计、示踪相关流量计、同位素吸水剖面测井仪组合到一起,使附加井温、压力、磁性定位等参数相互印证,得出准确的综合解释结果,从而为油田监测提供准确可靠的测井资料,具有一定的现实意义。     

Non-permutation flowshop scheduling in a supply chain with sequence-dependent setup times

In this paper, we consider a flowshop scheduling problem with sequence-dependent setup times and a bicriteria objective to minimize the work-in-process inventory for the producer and to maximize the customers' service level. The use of a bicriteria objective is motivated by the fact that successful companies in today's environment not only try to minimize their own cost but also try to fulfill their customers' need. Two main approaches, permutation and non-permutation schedules, are considered in finding the optimal schedule for a flowshop. In permutation schedules the sequence of jobs remains the same on all machines whereas in non-permutation schedule, jobs can have different sequence on different machines. A linear mathematical model for solving the non-permutation flowshop is developed to comply with all of the operational constraints commonly encountered in the industry, including dynamic machine availabilities, dynamic job releases, and the possibility of jobs skipping one or more machines, should their operational requirements deem that it was necessary. As the model is shown to be NP-hard, a metasearch heuristic, employing a newly developed concept known as the Tabu search with embedded progressive perturbation (TSEPP) is developed to solve, in particular, industry-size problems efficiently. The effectiveness and efficiency of the search algorithm are assessed by comparing the search algorithmic solutions with that of the optimal solutions obtained from CPLEX in solvable small problem instances.     

高星级酒店建筑能耗模型的简化探索

随着酒店产业的发展以及节能减排政策的推广,基于多元线性回归模型的建筑能耗模型已在酒店的能源管理以及节能项目的节能量结算过程中得到应用.但由于建模及验证过程专业性强,项目决策者对多元线性回归模型的接受程度较低.通过对模型参数选择的精炼以及表现形式的优化,形成一种基于多元线性回归模型的简化算法.将该简化算法用于高星级酒店能...     

多相流量计的原理与开发应用简介

多相流量技术就是将一种多相流量计直接安装在油气集输管线上，采用先进的测量技术，对油、气、水三相在不分离情况下进行连续、在线和自动计量，从而可以取代传统的由测试分离器及其辅助系统组成的计量装置，简化油气生产工艺流程，降低投资，减少操作成本。它可根据应用场合采用不同精度等级的多相计量装置，直接对油井产出液中的油、气、水三组分进行计量。     

An optimization approach for managing fresh food quality throughout the supply chain

One of the most challenging tasks in today's food industry is controlling the product quality throughout the food supply chain. In this paper, we integrate food quality in decision-making on production and distribution in a food supply chain. We provide a methodology to model food quality degradation in such a way that it can be integrated in a mixed-integer linear programming model used for production and distribution planning. The resulting model is applied in an illustrative case study, and can be used to design and operate food distribution systems, using both food quality and cost criteria.     

集值函数及向量值函数的两类线性算子逼近

本文得到了利用插值型线性算子列及积分型算子列逼近连续集值函数及连续向量值函数的收敛逼近阶。     

Using Genetic Algorithms to Estimate and Validate Bioeconomic Models: The Case of the Ibero-atlantic Sardine Fishery

Synopsis The Neo-classical approach to fisheries management is based on designing and applying bioeconomic models. Traditionally, the basic bioeconomic models have used pre-established non-linear functional forms (logistic, Cobb–Douglas) in order to try to reflect the dynamics of the renewable resources under study. This assumption might cause misspecification problems and, in consequence, a loss of predictive ability. In this work we intend to verify if there is a bias motivated by employing the said non-linear parametric perspective. For this purpose, we employ a novel non-linear and non-parametric prediction method, called Genetic Algorithms, and we compare its results with those obtained from the traditional methods.